Acidic is the correct spelling. The peanut oil in it will get rancid after time and produce acidic compounds (there is an expiration date on peanut butter). By all means use the creamy type if you are going to try this method (Ha Ha).
Remember that if you do get it unstuck, the PB might gum up the small oil passages. I would stick to the solvent based products with something to break up any rust.
